zebra: some more i/o optimizations

* Separate flush task from write task, so we can continue adding to the
  write buffer while it's waiting to flush
* Handle write errors sooner rather than later
* Only schedule a process job if we have packets to process
* Tweak zserv_process_messages to not reschedule itself and rely on
  zserv_read() to do so in all proper cases

Signed-off-by: Quentin Young <qlyoung@cumulusnetworks.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/zebra/zserv.h b/zebra/zserv.h
index a1b55bf8e..fc338d89e 100644
--- a/zebra/zserv.h
+++ b/zebra/zserv.h
@@ -72,6 +72,7 @@ struct zserv {
 	/* Threads for read/write. */
 	struct thread *t_read;
 	struct thread *t_write;
+	struct thread *t_flush;
 
 	/* default routing table this client munges */
 	int rtm_table;